"To violate your conscience is to commit moral suicide."
That provocative idea comes from an acquaintance of mine, Herman Keizer, a retired army (Colonel) Chaplain with forty years of military experience, whom the authors, Rita Nakashima Brock and Gabriella Lettini of Soul Repair: Recovering from Moral Injury after War quote.
Keizer has overstated his point. There is no recovery from suicide, but a person can recover from a moral injury. Hyperbole aside, Keizer is on target when he recognizes that violating one's conscience causes moral injury.
Moral injury is distinct from PTSD (Post-Traumatic Stress). PTSD is an emotional injury for which mental health professionals, sometimes assisted by clergy and others, provide treatment that may appropriately include prescription medicines. Moral injury effects one's conscience, spirit, or soul (take your choice, depending upon your view of anthropology). Healing for moral injury occurs through telling one's story, knowing that one is heard, rebuilding trust, reconnecting with people, and eventually experiencing forgiveness, self-forgiveness, and healing.
Explicit recognition of moral injury is relatively new, although authors going back at least to Homer (cf. The Iliad, the story of the warrior Homer's return from the Trojan war). Like PTSD and unlike wounds for which American soldiers receive the Purple Heart, moral injury is not a visible injury. However, that does not make the wound any less real or diminish the need for healing.
Although work on moral injury centers on warfighting, I believe that moral injury can occur in any situation in which a person violates her or his conscience. Not attempting to intervene to stop something a person recognizes as evil, afraid of the personal consequences of acting, seems likely to result in moral injury.
If you are interested in learning more about moral injury, I commend Brock and Lettini's book, Soul Repair, Jonathan Shay's book, Odysseus in America.